Insulin autoantibody are often the first autoantibody to appear prior to the development of Type 1A diabetes in children prospectively followed from birth. These autoantibody target one of four major islet autoantigens of autoantibody assays validated in CDC sponsored workshops of the Immunology of Diabetes Society (IDS). Early IDS workshops demonstrated that though multiple ELISA assays detected insulin antibodies following injection of subcutaneous insulin, standard ELISA formats were unable to detect insulin autoantibody of non-insulin treated new onset diabetic patients or individuals progressing to Type 1 diabetes. These standard ELISA assays bound insulin to solid substrates such as ELISA plates and attempted to detect anti-insulin antibody binding to the plate bound insulin. Unfortunately, these standard ELISA assays could not detect the antibodies predictive or diagnostic of Type 1 diabetes.
While radioactive assay methods are available for detecting the presence of insulin autoantibody, such methods are often costly and time consuming. Moreover, even utilizing radioactive insulin, one of the major problems of currently available assays is unacceptable variation in specificity and sensitivity between laboratories. Thus, accurate detection of human insulin autoantibody that are associated with the development of Type 1A diabetes has proven problematic.
Therefore, there is a continuing need for a reliable method of detecting insulin autoantibody.